LIFE LINE AMBULANCE LOST POWER WHEN DRIVING OVER RAILROAD TRACKS CAUSING SOMEONE'S DEATH**CC THE SOURCE OF THE SHUTDOWN WAS DETERMINED TO BE A SHORT TO THE GROUND CIRCUIT TO WHICH THE AMBULANCE CONSOLE/CONTROL SYSTEM WAS CONNECTED FOR IGNITION POWER. A SMALL CUT THROUGH THE INSULATION WIRE 295A WHICH ALSO SUPPLIED ACCESSORY POWER TO THE AM-FM IN DASH RADIO WAS DISCOVERED, WHICH EXPOSED A BARE SPOT OF COPPER WIRE WHICH APPARENTLY SHORTED TO THE GROUND ON THE ADJACENT METAL CASE OF THE RADIO. TESTING ESTABLISHED THAT GROUNDING WIRE 295A WHILE POWERED CAUSED A DEVICE OVERLOAD OF THE FREIGHTLINER VEHICLE TO IMMEDIATELY TRIP TO OPEN THE CIRCUIT, CAUSING THE AC FAN IN THE CAB TO SHUT OFF AND INITIATE THE 4 MINUTE TIMER TO SHUT DOWN THE 12 VOLT AMBULANCE CONSOLE. *JB